I recently had to install Samsung Kies on my Mac OS X Lion, and apparently the latest version doesn’t want to be installed on the Mac OS X Lion, stating that this OS is not supported. In order to get the latest version to work with your Mac OS X Lion, you’ll have to download the older version of Samsung Kies and install it.
Launch the Samsung Kies app, go to “Preferences > Update” and update your Samsung Kies app to the latest version. It’ll just take a few minutes depending on your internet connection speed. After a bit of churning, it should be installed and you’re good to connect your Samsung device.